Key Laboratory of Mesoscopic Chemistry of MOE, College of Chemistry and Chemistry Engineering, Nanjing University, Nanjing 210093, China.
J Hazard Mater. 2010 Aug 15;180(1-3):282-8. doi: 10.1016/j.jhazmat.2010.04.028. Epub 2010 Apr 14.
To study whether natural clinoptilolite could selectively capture Pb(2+) ion in the aqueous solution containing salt and glycine as well as nitrosamines, the natural zeolite was utilized in the complex solution with pH value of 1.2 in comparison with other porous materials such as zeolite NaZSM-5 and activated carbon. Clinoptilolite exhibited the highest capability in adsorbing Pb(2+) ion in the solution at 37 degrees C, achieving the capacity of 7 mg/g, two times more than that by other zeolites and six times over that by activated carbon, and the adsorption equilibrium could be achieved within 2h. The impacts of solid-liquid ratio, initial concentration of Pb(2+) and the competition of other metal ions or volatile nitrosamines on the adsorption were examined, and the change in Gibbs energy for the ion-exchanged of Pb(2+) ion by clinoptilolite was discussed, through which the ion-exchange process was proven to be spontaneous. Moreover, both the selectivity of clinoptilolite toward Pb(2+) ion in complex solution and the venial toxicity of clinoptilolite on the viability of RAW264.7 cells were investigated in this article.
为研究天然斜发沸石是否能在含有盐和甘氨酸以及亚硝胺的水溶液中选择性捕获 Pb(2+)离子，本研究利用天然沸石在 pH 值为 1.2 的复杂溶液中进行研究，并与其他多孔材料如沸石 NaZSM-5 和活性炭进行了比较。在 37℃下，斜发沸石在溶液中吸附 Pb(2+)离子的能力最高，达到 7mg/g，是其他沸石的两倍，是活性炭的六倍，吸附平衡可在 2h 内达到。考察了固液比、Pb(2+)初始浓度以及其他金属离子或挥发性亚硝胺竞争对吸附的影响，并通过讨论斜发沸石对 Pb(2+)离子的离子交换Gibbs 自由能变化，证明了离子交换过程是自发的。此外，本文还研究了斜发沸石在复杂溶液中对 Pb(2+)离子的选择性以及斜发沸石对 RAW264.7 细胞活力的轻微毒性。
